Minolta XE - 3 Measuring of CdS Resistance Value and Selection of Rp

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[3] Measuring of CdS Resistance Value and Selection of Rp
@Measuring instruments:
: Digital tester (Type 2507)
: Brightness box (Model L-222 or [.-223)
: Standard lens (50mm F 1.4)
:ND filter MINOLTA ND 50% for Adjustment
M@Measuring procedures:
1. As shown in the figure below, disconnect the soldering at Rp and terminal “C” of CdS (front
and back) of the printed base plate A (0432).
CdS front “C"
Cover with blackout curtain
to prevent external light.
Brightness box
|} Condition of body to
be measured:
«Distance ring: co
«Py button: depressed
(Pv SW: ON)
«Eye shutter: Shut
Rp
Remove
solder
while
letting
Rp
radiate.
(Use
a
pair
of
tweezers
or
the
like).
2.
Measuring
of
resistance
value
of
Rit
avo
(Resistance
value
should
be
within
88~340KQ).
Connect
between
“L"s
of
CdS
(front
and
back)
the
measuring
wire,
remove
the
solder
at
“H”
terminal
of
CdS
front
and
connect
the
digital
tester
to
“C”
of
CdS
(front
and
back).
Set
the
measuring
range
at
“9”
and
measure
the
resistance
value
at
Brightness
Ev
5
(ASA
100).
CdS front “H”
Digital tester (Range: 1)
{ 4 Measuring lead wire
3. Measuring of resistance value of Rit avs (Resistance value should be within 16~40KQ).
Carry
out
the
same
connection
for
CdS
as
described
above,
set
ND
filter
to
the
body
and
measure the resistance value at Brightness Ev 11 (ASA 100).
4.
Ruy
evs
Resistance
Value
Measurement
(Resistance
value
should
be
within
128~480KQ).
Maintain
the
brightness,
ND
filter
and
“C”
of
CdS
all
the
same
as
in
the
case
of
RL
Bvs,
solder the terminal “H” of CdS (front)
,
remov@
the
solder
of
measuring
wire
and
measure
and
measure
the
resistance
value.
CdS front “H"
Digital tester (Range: 1)
Measuring wire